The electronic circuitry (electronics) used to provide telephony, cable television and data communication, including wireless communication, etc., inevitably generates excess heat. Because such electronics can only function properly within a specified temperature range, e.g., -20.degree. C. to 70.degree. C., dissipation of the excess heat must be managed. A typical solution is to provide a thermal path from inside an electronics enclosure to large heat sinks located outside the enclosure. The heat sinks are sized to dissipate enough excess heat to maintain the electronics at a temperature at or below their maximum rated operating temperature when the external ambient temperature reaches an expected maximum, e.g., 46.degree. C.
The Background Art thermal management system of heat sinks is effective at keeping the operating temperature of the electronics at or below their maximum operating temperature. Unfortunately, the heat sink-based system becomes a liability at low temperatures. When the external ambient temperature falls below the required minimum for the electronics, they still must be maintained at or above the required minimum temperature. The heat sinks work contrary to this by dissipating the now-potentially useful heat generated by the electronics to outside the cabinet.
A Background Art solution to this problem has been to provide heaters that can be activated at lower temperatures to provide additional heat so that the resulting operating temperature stays at or above the specified minimum operating temperature of the electronics. But this has some disadvantages.
The power supply must be adequate to run the electronics as well as the heater circuitry, i.e., much larger than needed to merely run the electronics. Also, such heating circuitry is needed infrequently, for example on the order of 8-10 times per year. This type of solution is very costly in terms of the frequency of its use. A typical battery backup system for the electronics does not have the capacity to provide the tremendous power required by the heating circuitry. It is noted that power outages due to extreme temperatures can occur at very low temperatures as well as very high temperatures. The infrequency of the need for the heater circuitry, compounded by the likelihood of its unavailability due to power outages, makes this low temperature compensation scheme even less useful.